Messaging systems that provide voice, fax and/or e-mail messaging capabilities are well known. One example of such a messaging system is the Network Applications Platform commercially available from UNISYS Corporation (“the NAP system”). The NAP system is a configuration of hardware and software that provides data and voice processing capabilities through applications running on an enterprise server. The NAP system provides the interface between these applications, called network applications, and a telephone network. A voice mail application is an example of a network application that runs on the NAP platform. The voice mail application determines how calls to the messaging system are handled, what prompts are played to callers, and which features are available. Presently, the NAP is implemented on selected UNISYS A Series and ClearPath HMP NX computer systems running the MCP operating system. Further details of the structure and function of the NAP are provided in the following U.S. patents and pending applications, all of which are hereby incorporated by reference in their entireties:                U.S. Pat. No. 5,133,004, Jul. 21, 1992, “Digital Computer Platform for Supporting Telephone Network Applications”;        U.S. Pat. No. 5,138,710, Aug. 11, 1992, “Apparatus and Method for Providing Recoverability in Mass Storage Data Base Systems Without Audit Trail Mechanisms”;        U.S. Pat. No. 5,384,829, Jan. 24, 1995, “Digital Computer Platform for Supporting Telephone Network Applications”;        U.S. Pat. No. 5,323,450, Jun. 21, 1994, “Telephone Network Applications Platform for Supporting Facsimile Applications”;        U.S. Pat. No. 5,394,606, Feb. 20, 1996, “Multi-Lingual Prompt Management System for a Network Applications Platform”;        U.S. Pat. No. 6,058,166, May 2, 2000, “Enhanced Multi-Lingual Prompt Management in a Voice Messaging System With Support for Speech Recognition”;        U.S. patent application Ser. No. 08/964,744, filed Nov. 5, 1997, “Methods and Apparatus for Providing External Access to Executable Call Flows of a Network Application”;        U.S. patent application Ser. No. 08/987,571, filed Dec. 11, 1997, “Multiple Language Electronic Mail Notification of Received Voice and/or Fax Messages”;        U.S. patent application Ser. No. 09/451,077, filed Nov. 30, 1999, entitled “Method and Apparatus for Preventing Hung Calls During Protocol Violations in a Voice Messaging System”;        U.S. patent application Ser. No. 09/307,014, filed May 7, 1999, “Inter-system Call Transfer”; and        U.S. patent application Ser. No. 09/161,214, filed Sep. 25, 1998, “Multiple Node Messaging System Wherein Nodes Have Shared Access To Message Stores Of Other Nodes”.        
Network applications running on the NAP can provide enhanced services for telephone networks, such as Call Answer, Call Forward, Voice Store and Forward, Voice Mail, Bank By Phone, Emergency Number Facilities, Directory Assistance, Operator Assistance, Call Screening, Automatic Wake-up Services, and the like.
Messaging systems like the Unisys NAP are used to provide large-scale messaging services (supporting large numbers of subscribers). As such a messaging system may employ multiple NAP hosts that are geographically distributed to best suit processing demands. These hosts may be generally placed in cities to best accommodate total subscriber needs. Each NAP host typically serves the demand placed on it by its local network. However, network operators may seek to communicate between disparate NAP systems. For example, a first NAP system may be responsible for storing a subscriber's voice mailbox for his/her mobile phone, wherein the first NAP system is located in a first city. A second NAP system, located in a second geographically disparate city, may be responsible for storing the same subscriber's landline voice mailbox. A network operator operating the first and second NAP systems may wish to consolidate these voice mailboxes through communications between NAP hosts in a manner that appears to the subscriber as if the subscriber has a single voice mailbox for all of his/her phones. However, at present, the ability of one NAP host to communicate with another NAP host is limited. Hence, there is a need for a system and methods that allow for the communication of data among dispersed NAP systems. By having a distributed NAP environment, a travelling subscriber may be afforded the ability to access his/her data and/or services (e.g. Call Answer, Call Forward, Voice Store and Forward, Voice Mail, Bank By Phone, Emergency Number Facilities, Directory Assistance, Operator Assistance, Call Screening, Automatic Wake-up Services, and the like) by dialing a local number associated with the nearest NAP host. Currently, a travelling subscriber is relegated to calling the host computer on which his/her data and/or service actually resided. If the host computer is considerably remote to the subscriber, the subscriber may incur considerable calling expenses.
Further, messaging system operators may desire to consolidate messaging services between their fixed-wire and wireless messaging systems. By consolidating these services, messaging system operators may be able to offer single point of access to their subscribers for these services. For example, a messaging system operator may want to offer a consolidated voice mail box to a subscriber to consolidate voice mail between the subscriber's fixed-wire and wireless telephones. As such, a subscriber would no longer be relegated to maintain a voicemail box for his/her fixed-wire phone and another voicemail box for his/her wireless phone. Rather, the subscriber would have a consolidated voice mail box that would store messages for both of his/her fixed-wire telephone and wireless telephone. From a system standpoint, however, these services may be located in disparate messaging systems on different NAP platforms. As such, these NAP systems would be required to cooperate to efficiently share and process required data. Current NAP systems, however, are unable to efficiently realize this contemplated consolidation scheme.
From the foregoing it may be appreciated that there exists a need for a distributed network applications platform (NAP) that allows local access to data residing on remote host computers to realize a number of advantages that currently escape messaging systems.